Solvent for dyestuffs



UNITED STATES PATENT OFFICE.

HERBERT A. FOLSOM, 0F PROVIDENCE, RHODE ISLAND.

SOLVENT FOR DYESTUFFS.

No Drawing.

To all whom it may concern Be it known that l, HERBERT A. FoLsoM, a citizen of the United States, residing at Providence, in the county of Providence and State of Rhode Island, have invented certain new and useful Improvements in Solvents for Dyestuffs, of which .the following is a specification.

My invention relates to solvents for colorin matter.

%lertain colors, such as vat colors and sulfur colors are insoluble in water. It is necessary, in order that these colors be used to dye a material, that they bemade soluble. lt-is also important that colors after being dissolved be maintained in solution.

To the above ends essentially my invention consists in such materials and in such combinations of materials, and in such steps and combinations of steps as fall within the scopeozt' the appended claims.

I have discovered that sulfite liquor, which occurs as a by-product in the sulfite process of paper pulp manufacture, is a suitable agent for dissolving and blending vat colors and sulfur colors tor dyein and printing. By vat colors is meant indlgo, indigo and anthracene derivatives, and modifications of the derivatives.

In utilizing my invention any one of the enumerated coloring matters, either in powder or paste form, is subjected to the action of sulfite wasteliquor in alkaline solution.

. Specification of Letters Patent. Patented May 24., 1921.. Application filed. February 25, 1921. Serial No. M73884.

The sulfite Waste liquor employed is the by-product of the sulfite process of paper pulp manufacture. to any alkali or salt having an alkaline ac- Alkaline herein refers v tion. The amount of the sufite liquor and the amount and kind ofalkali may be varied with advantage in the treatment of individual coloring matters, and upon different materials.

The following is an illustrative formula for dissolving synthetic indigo or a vat color of indigo derivation: By eight, 2 parts sulfite Waste liquor, on dry basis, dissolved in 5 parts water; into which is stirred 1 part granulated caustic soda, first, and then 2 parts of 100% indigo or indigo derivative. This mixture is stirred and'heated to about 135 degrees Fahrenheit, and then diluted and cooled to a volume of 20 parts and a temperature of about 110 degrees which completes the dye liquor.

I claim 1. As a solvent for vat colors and sulfur colors, a sulfite waste liquor in alkaline solution. a

2. A process of dissolving vat colors and sulfur colors consisting in mixing the color to be dissolved with water, an alkali, and a sulfite waste liquor.

' In testimony whereof Ihave affixed my signature.

' HERBERT A. FOLSOM. 

